General Site Information
Site ID:US-Tw3
Site Name:Twitchell Alfalfa
Tower Team: PI: Dennis Baldocchi <> - University of California, Berkeley
FluxContact: Sam Chamberlain <> - UC Berkeley
Technician: Daphne Szutu <> - UC Berkeley
Technician: Joe Verfaillie <> - University of California, Berkeley
Affiliate: Patty Oikawa <> - University of California, Berkeley
Elevation (m):-9
IGBP:CRO (Croplands)
Climate Koeppen:Csa (Mediterranean: mild with dry, hot summer)
Mean Annual Temperature (degrees C):15.6
Mean Annual Precipitation (mm):421
Data Products: AmeriFlux BASE Dataset
FLUXNET2015 Dataset
Data Availability: AmeriFlux BASE:   3 years (Duration: 2013 - 2015)
FLUXNET2015:   2 years (Duration: 2013 - 2014)
Data Downloads to Date: AmeriFlux BASE:   283 unique downloads
FLUXNET2015:   764 unique downloads
Data DOIs: AmeriFlux BASE DOI: 10.17190/AMF/1246149
Description:The Twitchell Alfalfa site is an alfalfa field owned by the state of California and leased to third parties for farming. The tower was installed on May 24, 2013. This site and the surrounding region are part of the San Joaquin - Sacramento River Delta drained beginning in the 1850's and subsequently used for agriculture. The field has been alfalfa for X years…., Crop rotation occurs every 5-6 years. The site is harvested by mowing and bailing several times per year. The field is fallow typically between November and February. The site is irrigated by periodically-flooded ditches surrounding the field. The site is irrigated by raising, and subsequently lowering the water table??
Acknowledgments:Biometeorology Lab, University of California, Berkeley, PI: Dennis Baldocchi
Site image(s):
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Publications relevant to understanding the site
Baldocchi, D., C. Sturtevant, and C. Fluxnet. 2015. Does day and night sampling reduce spurious correlation between canopy photosynthesis and ecosystem respiration? Agricultural and Forest Meteorology 207:117-126. Primary_Citation
Oikawa, P. Y., C. Sturtevant, S. H. Knox, J. Verfaillie, Y. W. Huang, and D. D. Baldocchi. 2017. Revisiting the partitioning of net ecosystem exchange of CO2 into photosynthesis and respiration with simultaneous flux measurements of 13CO2 and CO2, soil respiration and a biophysical model, CANVEG. Agricultural and Forest Meteorology 234–235:149-163. Alt_Citation

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